Hand held spray gun

ABSTRACT

A hand held fluid flow control assembly especially adapted for industrial cleaning applications wherein chemicals such as an acid or detergent may be selectively added to a jet stream of water during a washing operation or alternatively, pure water may be made to flow during a rinse operation. The device includes an input connection adapted to be connected by a length of hose to a source of water under high pressure and an output wand for directing a fluid stream at an object to be cleaned. Connected between the inlet and the output wand are first and second paths along with a valve which can be manually positioned to allow the high pressure water to flow either through the first path or the second path or to block both paths completely. A venturi-type aspirator or injector is disposed in one path and connected to the suction inlet thereof are a pair of gate valves which control the introduction of first and second chemicals from separate reservoirs into the fluid stream as it passes through the first path. The input connections to the first and second gate valves are connected to the chemical reservoirs by means of predetermined lengths of flexible hose. As such, all of the controls necessary for effecting the washing and rinsing operation are self-contained in the hand held unit.

United atet [191 Trapp 1 Nov. 26, 1974 1 i HAND HELD SPRAY GUN [76] Inventor: James A. Trapp, 2425 W. County Rd. C-2, Saint Paul, Minn. 55 113 22 Filed: Mar. 25, 1974 21 Appl. No.: 454,448

[52] U.S. Cl 239/113, 239/119, 239/307 [51] Int. Cl B05b 15/02 [58] Field of Search 239/112, 113, 119, 304, 239/305, 307, 317, 375

[56] References Cited UNITED STATES PATENTS 2,847,318 8/1958 Dowlen et a1 239/113 X 3,690,557 9/1972 Higgins 239/112 Primary Examiner-M. Henson Wood, ,lr. Assistant Examiner-Michael Mar Attorney, Agent, or Firm-Thomas J. Nikolai [57] ABSTRACT A hand held fluid flow control assembly especially adapted for industrial cleaning applications wherein chemicals such as an acid or detergent may be selectively added to a jet stream of water during a washing operation or alternatively, pure water may be made to flow during a rinse operation. The device includes an input connection adapted to be connected by a length of hose to a source of water under high pressure and an output wand for directing a fluid stream at an object to be cleaned. Connected between the inlet and the output wand are first and second paths along with a valve which can be manually positioned to allow the high pressure water to flow either through the first path or the second path or to block both paths completely. A venturi-type aspirator or injector is disposed in one path and connected to the suction inlet thereof are a pair of gate valves which control the introduction of first and second chemicals from separate reservoirs into the fluid stream as it passes through the first path. The input connections to the first and second gate valves are connected to the chemical reservoirs by means of predetermined lengths of flexible hose. As such, all of the controls necessary for effecting the washing and rinsing operation are self-contained in the hand held unit.

2 Claims, 2 Drawing Figures HAND HELD SPRAY GUN BACKGROUND OF THE INVENTION This invention relates generally to a chemical-water mixing and dispensing apparatus and more particularly to a hand-held device suitable for industrial washing applications.

In heavy industrial cleaning operations such as may be involved in the washing of trucks, trains, buildings, etc., which become incrusted with dirt, oils, greases and other sludge, it is generally desirable to apply a series of chemicals during the washing operation which serve to break down this grime so that it can be rinsed clean with clear water. For example, it is often desirable to go over the surface to be cleaned with a solution of water and a suitable acid or other chemical as an initial step before a detergent is applied. The application of the acid and detergent solutions serves to loosen and breakdown any chemical bonds between the grime to be removed and the surface being cleaned so that during a rinse operation all such particles will be removed. Further, itis desirable that the nozzle through which the chemicals and rise water flow be remote from the reservoir or supply of chemicals and water and connected thereto by means of flexible hose so that the operator is free to move about more readily. This arrangement necessitates having the controls for governing the flow of chemicals and water located near the output nozzle in a hand-held unit. This obviates the necessity of setting down the output nozzle and returning to some remote site to effect a change over fromone chemical to another or to a rinse water.

The washing apparatus of the present invention provides all of these desirable features. In a single handheld unit means are provided for first producing an acid-water stream, for subsequently producing a detergent-water stream and for finally allowing clear water to flow during a rinse cycle. Further, the unit of this invention allows a complete stoppage of fluid flow when desired.

It is accordingly the principle object of this invention to provide a rugged, hand-held spray gun device with control means for permitting an operator to selectively provide a chemical wash and a clear water rinse.

Another object of the invention is to provide a spray gun assembly adapted to handle corrosive chemicals flowing under high pressures.

Still another object of the invention is to provide a spray gun assembly in which all controls are located in the gun assembly which, in turn, is connected to a water supply and chemical reservoirs by means of flexible hosing.

These and other objects of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawings which illustrate the preferred embodiment of the invention wherein:

FIG. 1 is a pictorial view of the apparatus embodying the invention; and

FIG. 2 is a cross-sectional view of the Venturi block assembly used in the embodiment of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1, there is indicated generally by numeral the hand-held fluid control washer assembly of the present invention. The assembly includes a Venturi block 12 which may be cast or otherwise formed from a suitable material such as metal or plastic, the details of which are more clearly illustrated in the cross-sectional diagram of FIG. 2. As is illustrated in FIGS. 1 and 2, the Venturi block includes an externally threaded, male input connection 14 and an internally threaded, female output connection 16. Disposed between the inlet connection 14 and the outlet connection 16 and integrally. formed in the Venturi block assembly 12 are first and second apertures 18 and 20 which are drilled or otherwise formed in the bottom of the Venturi block assembly and which communicate with inlet connections (not shown) to which are attached first and second flexible hoses 22 and 24.

Also formed within the Venturi block assembly 12 is a bore 26 which is substantially concentric with the cylindrical input connection 14 and which extends for a predetermined distance into the Venturi block 12. At the internal terminus of the bore 26 is an extension thereof identified by numeral 28 which is concentric with the bore 26 but of a reduced diameter. For example, the diameter of the bore 26 may be 0.312 inches while the diameter of the extension 28 may be 0.234 inches. The reduced diameter extension of bore 26 forms a Venturi-type injector within the block 12.

The bore extension 28 is tapered to define a throat 30, which in the preferred embodiment may have a diameter of 0.0625 inches. The throat 30 is connected to the internally threaded female output connection 16 by a tapered bore 32 which, at its output terminus, may have a diameter of, for example, 0.200 inches.

Communicating at right angles to the tapered bore 32 is a cylindrical port 34 formed through the bottom of the Venturi block 12 to which is connected a bypass tube 36 (FIG. 1). While the details of the connections to the ports 18, 20 and 34 are not shown in detail, in the preferred embodiment there is formed in the bottom of the block 12 an internally threaded bore which may accept an externally threaded hose or tube connector of conventional design.

The Venturi block 12 also includes first and second projections 36 and 38 which extend generally at right angles to the center line of the bore 26 and output port 16. Each of the projections 36 and 38 has an externally threaded cylindrical projection 40 and 42 as well as concentric cylindrical bores 44 and 46. The bores 44 and 46 are provided with threads over a predetermined length thereof and the orifices l8 and 20 also communicate with the bores 44 and 46. The bores 44 and 46 are also tapered so as to have, for example, a included angle as indicated by numerals 48 and 50. As will be explained more fully hereinbelow, the internally threaded bores 44 and 46 are adapted to receive the stems of a pair of gate valves 52 and 54 (FIG. 1) having sealed caps 56 and 58 threadably secured to the external threads on the projections 40 and 42. The gate valves, in turn, each have a valve seat which is tapered at the same angle as the taper of bores 48 and 50.

The bores 44 and 46 communicate with the extension 28 of the cylindrical input bore 26 by way of orifices 60 and 62 which extend from the tapered ends of the segments 48 and 50 into the chamber defined by the extension 28. Thus, when the stems of the valves 52 and 54 are advanced into the bores 44 and 46 so that the valve seats tightly abut the tapered segments 48 and 50, the flow-path from the orifices l8 and 20 into the reduced diameter extension 28 will be blocked. Alternatively, when the valve stems are rotated in a counterclockwise direction, the tapered valve seats will be retracted from their closed position in abutment with the tapered segments 48 and 50, allowing fluid to flow from the orifices l8 and into the extension chamber 28.

Referring again to FIG. 1, there is shown a conventional ball valve assembly 64 having an input port at the bottom thereof to which is secured an input hose 66 by means of a hose connector 68. A ball valve assembly readily suitable for use in the preferred embodiment of the invention is manufactured and sold by the Whitey Company of Oakland, California and reference may be made to their catalog number W-37l copyright 1971 by the Whitey Company for further design details of this three-way ball valve assembly.

The three-way ball valve assembly 64 has first and second outputs 70 and 72 and a ball valve actuator handle 74. The output 70 is threadably secured to the external threads 14 on the Venturi block 12 while the output 72 from the ball valve 64 is connected to the hose 36 which, as mentioned previously, communicates with the orifice 34 (HO. 2). When the actuator handle 74 is in the position illustrated, fluid under pressure from a source connected to the hose 66 will pass through the valve 64 and into the cylindrical bore 26 of the Venturi block 12. When the handle 74 is rotated 180, the fluid will pass from the inlet connection 68 and through the bypass tube 36 into the orifice 34. When the handle 74 is rotated from the position illustrated by only 90, the internal ball valve completely blocks the flow of fluid from the input connection 68 to either the output connection 70 or the output connection 72.

Finally. in completing the description of the construction of the fluid flow control assembly of the present invention, there is shown an output wand 76 having its input threadably secured to the internally threaded output port 16 of the Venturi block assembly 12. The wand 76 serves to direct the flow of fluid passing through the assembly onto the item to be treated.

OPERATION The fluid flow control assembly of the present invention is readily suited for use in washing surfaces badly covered with grime such as dirt, oils and greases, chemicals, etc. For example, the device of the present invention is readily suitable for washing of automotive vehicles such as cars, trucks, etc., but limitation thereto is not intended.

In operation, the input hose 66 is connected to a source of water under high pressure, for example, l,000 pounds per square inch. Hoses 22 and 24 are respectively connected to two separate unpressurized supplies of cleaning chemicals which may be specially formulated for a particular application. For example, the hose 22 may connect to a reservoir of soap or other detergent while hose 24 may connect to a reservoir of a suitable cleaning acid.

in a typical washing operation, the source of high pressure water as well as the reservoirs for the chemicals may be located a substantial distance from the vehicle being cleaned by means of the hoses 22, 24 and 66. First, the operator would close the gate valves 52 and 54 and turn the handle 74 to the position indicated in FIG. 1 so that the high pressure water stream will pass from the input hose 66, through the ball valve assembly 64 and through the bore 26, the extension 28, the tapered bore 32 and from there out of the wand 76 onto the surface to be cleaned. The gate valves 54 and 56 being in their closed position, only water will exit from the wand 76. This high pressure stream of water is used to dislodge large particles or chunks of grime from the surface being cleaned preparatory to the application of the detergent and acid.

Following the initial clear water wash operation, the operator, without having to return to the location of the chemical reservoirs, may direct a mixture of acid and water onto the vehicle by merely rotating the ball valve control handle 74 to the position illustrated in FIG. 1 and by opening the gate valve 52, while leaving the gate valve 54 in its closed position. With this arrangement, the high pressure water from the source connected to the hose 66 passes through the ball valve assembly 64 and into the input bore 26 of the Venturi block 12. As the high pressure water passes through the bore 26 and into the extension 28 which is of a reduced diameter from that of bore 26, the velocity of the fluid is increased and based upon Venturis principle, there will be an accompanying reduction in the pressure existing in the chamber defined by the extension 28. Because of the reduced pressure in chamber 28, acid contained within the reservoir to which hose 24 is connected will be drawn up through the hose 24, through the orifice 20, and the open gate valve into the chamber 28 where it will be combined with the high pressure water before exiting through the tapered bore 32 and the wand 76.

After the item being cleaned has been treated with the acid in the manner described, the operator merely closes the gate valve 52 and opens the gate valve 54, leaving the ball valve actuator handle 74 in the same position. As a result, again the low pressure created in the chamber 28 by the high velocity water stream passing therethrough will cause the detergent contained within a reservoir to pass through the hose 22, the orifice l8 and the open gate valve into the mixing chamber 28 where it is combined with the high velocity water stream and directed out of the Venturi block through the tapered bore 32 and through the wand 76 onto the surface being cleaned.

Following this latter operation, the operator again closes both of the gate valves 52 and 54 to shut off the flow of chemicals again allowing only high pressure water to flow through the hose 66, the ball valve 64, the Venturi block 12 and the wand 76 for a final rinsing operation.

Because the acid and detergent employed may have a corrosive effect on the gate valves and the Venturi block itself as well as the hoses 22 and 24, means are provided for back washing this entire assembly. Following the conclusion of the washing operation, the hoses 22 and 24 are removed from their respective reservoirs and the handle 74 is rotated from the position illustrated, causing high pressure water to flow through the ball valve assembly 64, the bypass tube 36 and the orifice 34 into the Venturi block 12. If the gate valves 52 and 54 are now open, even though a majority of the water being supplied will pass out through the wand 76 a fraction thereof will back flow through the tapered bore 32, the mixing chamber 28, the gate valve bores 44 and 46 and the orifices 18 and 20 communicating therewith and back through the chemical supply hoses 22 and 24 to rinse them out preparatory to shut down.

Of course, at any stage of the washing operation if the operator desires to cut off the flow of fluid through the hand-held assembly 10, he need merely rotate the ball valve actuator handle 74 by 90 to thereby block the incoming high pressure water in hose 66 from exiting from either outlet connection 70 or outlet connection 72.

There has thus been described a highly efficient spray gun apparatus which permits the controlled flow and mixture of a plurality of chemicals with a water jet as well as means for applying clear water during rinsing operations from a location remote from the locations of the chemical reservoirs and the high pressure water source. it will be apparent to those skilled in the art that the invention, as described herein, is susceptible to variation, modification and change and therefore the scope of the invention is to be determined by the appended claims.

What is claimed is:

l. A washing apparatus comprising:

a. an inlet means adapted to be connected to a high pressure water supply;

b. a tubular wand;

c. first and second fluid flow paths connected between said inlet means and one end of said tubular wand;

(1. means disposed between said inlet means and said first and second fluid flow paths for selectively directing the flow of water alternatively through said first path, said second path or blocking the flow of water through either said first or second paths;

e. means disposed in said first fluid flow path for allowing the introduction of chemicals therein when water flows through said first fluid flow path; and

f. means including first and second valves connected between said last named means and first and second reservoirs which are adapted to contain chemical solutions.

2. A washing apparatus comprising:

a. an inlet means adapted to be connected to a high pressure water supply;

b. a tubular wand having a spray nozzle on one end thereof;

c. first and second fluid flow paths connected between said inlet means and the other end of said tubular wand;

d. valve means disposed between said inlet means and said first and second fluid flow paths for directing the flow of water alternatively through said first path, said second path or blocking the flow of water through either said first or second paths;

e. a venturi-type injector disposed in said first fluid flow path for producing a partial vacuum at an input orifice when water flows through said first fluid flow path; and

f. means including first and second gate valves connected between said input orifice and first and second reservoirs which are adapted to contain chemical solutions to be mixed with the water flowing through said first fluid flow path. 

1. A washing apparatus comprising: a. an inlet means adapted to be connected to a high pressure water supply; b. a tubular wand; c. first and second fluid flow paths connected between said inlet means and one end of said tubular wand; d. means disposed between said inlet means and said first and second fluid flow paths for selectively directing the flow of water alternatively through said first path, said second path or blocking the flow of water through either said first or second paths; e. means disposed in said first fluid flow path for allowing the introduction of chemicals therein when water flows through said first fluid flow path; and f. means including first and second valves connected between said last named means and first and second reservoirs which are adapted to contain chemical solutions.
 2. A washing apparatus comprising: a. an inlet means adapted to be connected to a high pressure water supply; b. a tubular wand having a spray nozzle on one end thereof; c. first and second fluid flow paths connected between said inlet means and the other end of said tubular wand; d. valve means disposed between said inlet means and said first and second fluid flow paths for directing the flow of water alternatively through said first path, said second path or blocking the flow of water through either said first or second paths; e. a venturi-type injector disposed in said first fluid flow path for producing a partial vacuum at an input orifice when water flows through said first fluid flow path; and f. means including first and second gate valves connected between said input orifice and first and second reservoirs which are adapted to contain chemical solutions to be mixed with the water flowing through said first fluid flow path. 